Battery storage systems are emerging as one of the key solutions for effectively integrating high rates of solar and wind renewable energy into power systems worldwide. A new analysis from the International Renewable Energy Agency (IRENA) shows how electricity storage technologies can be used for a variety of applications in the power sector, from e-mobility and back-of-meter applications to utility-scale use cases.

For example, grid-scale electricity batteries can enable more renewables to enter the grid by storing overproduction and tightening renewable energy output. Also, especially when paired with renewable generators, the batteries help provide reliable and cheaper electricity in isolated grids and grid-independent communities, otherwise relying on expensive imported diesel fuel for electricity generation.

Currently, grid-scale battery storage systems are mainly used in Australia, Germany, Japan, the UK, the USA and other European countries. One of the larger systems in terms of capacity is the Tesla 100 MW/129 MWh Li-ion battery storage project at Hornsdale Wind Farm in Australia. A high-end demonstration project in the US State of New York using a 4 MW/40 MWh battery storage system showed that the operator can reduce nearly 400 hours of congestion in the power grid and save up to US$2.03 million in fuel costs.

In addition, several island and off-grid communities have invested in large-scale battery storage to balance the grid and store excess renewable energy. Globally, energy storage deployment in emerging markets is expected to increase by more than 40% each year until 2025.

Currently, electricity-scale fixed batteries dominate global energy storage. However, by 2030, small-scale battery storage is expected to increase significantly. Installation of counter-back (BTM) batteries globally is on the rise. This increase is due to the falling costs of battery storage technology, due to the increasing consumer market and the development of electric vehicles (EVs) and plug-in hybrid EVs (PHEVs). In Germany, for example, 40% of recent rooftop solar PV applications have been installed with BTM batteries. With 21,000 system installations in the country in 2017, Australia aims to reach one million BTM battery installations by 2025. Overall, total battery capacity in fixed applications can increase from the current estimate of 11 GWh by 180 to 420 GWh.